1. Field of the Invention
The present application relates generally to communication processing systems and more particularly to an expandable communications node providing processing of integrated voice, data and fax.
2. Description of the Prior Art
Prior art communications switching systems typically consist of a plurality of communications processing nodes connected via telephone lines, local area networks or wideband span bands. The number of nodes and processing capacity of each node is usually based on the present and, to some degree, the anticipated near term growth in the number of mainframes, users, terminals, voice trunks and other devices supplying data to the nodes. Each node typically contains at least (a) one or more user interfaces for handling user input, output and reformatting, (b) one or more network interfaces to handle the input, output and reformatting of data from the network (c) a switch matrix to interconnect the appropriate user interface with the appropriate network interface, and (d) a processor for controlling the switch matrix connections and, in some systems, for handling packet processing and other overhead functions.
Prior art nodes commonly are not designed for and have little, if any, provision for incremental, modular increases in processing capacity to meet increasing user needs. Adding additional system functionality or enlarging the capacity of the system when a node can no longer meet user demands typically requires significant reconfiguration of the existing system or complete replacement of the existing nodes with nodes of larger capacity. Either of these approaches usually results in significant undesirable disruption in system services. Furthermore, the purchase and installation of nodes that have sufficient flexibility and reserve processing power to handle substantial future growth in demands on the system is generally not a practical solution, even if such nodes are available, because of the extra expense involved in purchasing excess capacity and the uncertainty of trying to accurately forecast demand in the future.
The present invention relates to a novel circuit for resolving the above and other prior art problems.